Method of treating the finger-bars for mowers.



B. R. BENJAMIN. METHOD OF TREATING THE FINGER BARS FOR MOWERS.APPLICATION FILED JUNE 30, 1910.

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KTNETED TATE FATENT GFFEQE.

BERT R. BENJAMIN, OF OAK PARK, ILLINOIS, ASSIGNOR TO INTERNATIONAL HAR-VESTER COMPANY, A CORPORATION OF NEW JERSEY.

METHOD OF TREATING THE FINGER-BARS FOR MOWERS.

Specification of Letters Patent.

Patented June 20, 1911.

Application filed. June 30, 1910. Serial No. 569,623.

To all whom it may concern:

Be it known that I, BERT R. BENJAMIN, a citizen of the United States,residing at Oak Park, in the county of Cook and State of Illinois, haveinvented a certain new and useful Method of Treating the Finger-Bars forMowers, of which the following is a specification.

My invention relates to a method of treat ing the finger bars for mowerswhereby the stiffness thereof is materially increased and theserviceability of the bar in operation lengthened.

It consists in a combined heat and mechanical treatment of the bar inorder to stiffen it in a manner to effectively resist strains to whichit may be subjected in operation; the object of my invention being toproduce a bar having a maximum of rigidity with a minimum weight. Thisobject I attain by means of the method hereinafter described andillustrated by the accompanying drawings, in which Figure 1 represents aplan View of the blanks from which the finger bars are formed; Fig. 2represents the blank after it has been heated and curved from end toend; Fig. 3 represents the bar after pressure has been applied tostraighten it; and Fig. 4t is a plan view of the finished article withthe fingers attached.

The finger bars for mowers as commonly constructed are usually made fromflat slabs of steel having a uniform thickness through out their length,a straight front edge to which the fingers are attached, and a gradually reduced width from the stubbleward end of the bar toward thegrainward end thereof, the stubbleward end of the bar being secured toan inner shoe that is pivotally attached to the coupling frame of amower in a manner to rise and fall as it follows the uneven surface ofthe ground, the outer end of the bar being secured to a shoe that ridesupon the ground. Means are provided upon the mower frame for raising thefinger bar and cutting apparatus in order that it may pass over whatwould otherwise ob struct it, and also to raise the finger bar to avertical position in some constructions. As the finger bar is connectedat its inner or stubbleward end only with the supporting and elevatingmeans, the weight thereof, wit-h the associated parts of the cuttingapparatus carried thereby, has a tendency to cause the bar to bend ordroop downward at its outer or grassward end, causing undue frictionbetween the sickle and fingers and otherwise impairing the efficiency ofthe ma chine.

To counteract the above noted structural defects and to provide a fingerbar so constituted that it will successfully resist severe strainsincident to continued use thereof, is accomplished by the practice of myimproved method of treating the bar, that consist in: first: heating thebar to a degree of temperature whereby it may be readily bent thengiving it a gradual curve from end to end in a direction opposite tothat in which a maximum degree of rigidity is required and to that ofthe active force or elements tending to bend the bar downward at itsgrassward end in the operation of the machine; second: by cooling thebar while it is maintained in its curved form, then reducing the curveby pressure while the bar is in a cool state and until the bar issubstan tially straight and a permanent set is imparted thereto.

vVhat I claim as my invention, and de sire to secure by Letters Patent,is:

The method of treating a finger bar for mowers, consisting in heatingand bending it to a predetermined degree of curvature in a directionopposite to that in which maximum rigidity is required, cooling the barwhile maintained in its curved form and then while in a cool statestraightening it by pressure to impart a permanent set thereto.

BERT R. BENJAMIN.

Witnesses:

RAY D. LEE, LUD HOLLAND-LETZ.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

